The disclosure relates to a boat drive with an electric motor which drives a propeller, and with a control device for controlling the electric motor, wherein the control device can be brought to a neutral position in which the propeller is not driven, and wherein the control device can be brought to at least one operating position in which the propeller is rotated.
Outboard motors for boats are often controlled by means of a tiller attached to the outboard motor. The speed of rotation is usually varied by turning the twist grip on the tiller. In combustion motors, the transmission of force from the motor to the propeller is interrupted at idle, usually by means of a centrifugal clutch. This is necessary in order that the propeller does not immediately begin to rotate, and thereby drive the boat, when the motor starts. Only when the motor's rotational speed is increased by turning the throttle grip is the force from the motor transmitted to the propeller and the boat driven by the rotation of the propeller.
Because combustion motors can rotate in only one direction, the direction of rotation of the propeller must be changed by means of a reversing transmission. Using a shift lever, the propeller can be switched back and forth between its two directions of rotation. Thus the propeller can rotate forwards in one position of the shift lever, and in reverse in the other position of the shift lever, without the need for the combustion motor to change its direction of rotation to achieve this. To change the propeller's direction of rotation, it is only necessary to throttle back and then, when the motor is at idle, change the position of the shift lever of the reversing transmission.
In the case of an outboard motor with an electric drive, the selector switch for forward and reverse gears can be dispensed with. The propeller's direction of rotation can be governed by the direction of the current. An idle mode and a centrifugal clutch are also unnecessary, since when the propeller is not in motion the electric motor is also at a standstill. This also means, however, that if the throttle is unintentionally opened, the propeller begins to rotate unless a further safety device is provided.
Electric motors deliver high torque even at low rotational speeds. Particularly in the case of high-performance electric outboard motors, there is a risk that inadvertent twisting of the throttle grip will set the boat in uncontrolled motion.
An object of the present invention is therefore to improve an electric boat drive such that unintended opening of the throttle is prevented.
Other features and advantages will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the presently described embodiments.